Implementation and validation of a risk stratification method at The Ottawa Hospital to guide thromboprophylaxis in ambulatory cancer patients at intermediate-high risk for venous thrombosis

Background: Cancer patients have a significantly higher risk of developing a venous thromboembolism (VTE) compared to non-cancer patients and yet studies suggest VTE risk among ambulatory cancer patients varies widely. Recently, predictive models capable of risk-stratifying a broad range of ambulatory cancer outpatients have been developed. Using the Khorana model a score of 2 was intermediate-high risk for VTE as reported by Ay and colleagues. However, validation in a broader population and methods to implement this model seamlessly into clinical practice are lacking. Objective: To create and assess the feasibility of an innovative computerized Care Process Management System (CPMS) that would automatically access electronic medical records to calculate in real-time the risk of VTE in patients with active cancer using an established VTE risk scoring system. Methods: A prospective observational study of all newly referred cancer patients at the Ottawa Regional Cancer Center, the sole cancer care provider for 1.2 million inhabitants, was conducted. Results: 699 new referrals were determined to have a cancer diagnosis for the first time as identified by the computer software and qualified for our study and 580 were eligible. In total 25% had intermediate-high risk for VTE and during the 3-month follow up period, 16 of the 143 (11%) developed a VTE which further validates the Khorana model for identifying intermediate-high risk patients. Of the 437 patients in the low risk group 19 (4%) developed a VTE. Conclusion: Newly diagnosed cancer patients can be readily stratified into intermediate-high and low risk of VTE using our novel CPMS system. This innovative tool can be used to facilitate customized management decisions regarding VTE prophylaxis for intermediate-high risk patients based their individual risk factors. (C) 2015 Elsevier Ltd. All rights reserved.